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Related papers: Reflexive polytopes arising from perfect graphs

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It is a famous open question whether every integrally closed reflexive polytope has a unimodal Ehrhart delta-vector. We generalize this question to arbitrary integrally closed lattice polytopes and we prove unimodality for the delta-vector…

Combinatorics · Mathematics 2011-10-18 Jan Schepers , Leen Van Langenhoven

We study the question of when 0-1 polytopes are normal or, equivalently, having the integer decomposition property. In particular, we shall associate to each 0-1 polytope a labeled hypergraph, and examine the equality between its Ehrhart…

Commutative Algebra · Mathematics 2014-09-08 Huy Tai Ha , Kuei-Nuan Lin

We study the linear extension complexity of stable set polytopes of perfect graphs. We make use of known structural results permitting to decompose perfect graphs into basic perfect graphs by means of two graph operations: 2-join and skew…

Combinatorics · Mathematics 2018-11-20 Hao Hu , Monique Laurent

Beck et. al. characterized the grid graphs whose perfect matching polytopes are Gorenstein and they also showed that for some parameters, perfect matching polytopes of torus graphs are Gorenstein. In this paper, we complement their result,…

Combinatorics · Mathematics 2008-03-11 Makoto Tagami

The perfectly matchable subgraph polytope of a graph is a (0,1)-polytope associated with the vertex sets of matchings in the graph. In this paper, we study algebraic properties (compressedness, Gorensteinness) of the toric rings of…

Combinatorics · Mathematics 2023-07-18 Kenta Mori

Graph polytopes arising from vertex-weighted graphs were first introduced by B\'ona, Ju, and Yoshida. We prove a conjecture stating that for any simple connected graph, the numerator polynomial of the Ehrhart series of its graph polytope is…

Combinatorics · Mathematics 2026-04-13 Feihu Liu

A lattice Delaunay polytope D is called perfect if it has the property that there is a unique circumscribing ellipsoid with interior free of lattice points, and with the surface containing only those lattice points that are the vertices of…

Number Theory · Mathematics 2007-05-23 Robert Erdahl , Andrei Ordine , Konstantin Rybnikov

A long-standing open conjecture in combinatorics asserts that a Gorenstein lattice polytope with the integer decomposition property (IDP) has a unimodal (Ehrhart) $h^\ast$-polynomial. This conjecture can be viewed as a strengthening of a…

Combinatorics · Mathematics 2018-06-04 Benjamin Braun , Robert Davis , Liam Solus

We provide a Minkowski sum decomposition of marked chain-order polytopes into building blocks associated to elementary markings and thus give an explicit minimal set of generators of an associated semi-group algebra. We proceed by…

Combinatorics · Mathematics 2020-01-28 Xin Fang , Ghislain Fourier , Christoph Pegel

Inspired by computational complexity results for the quantified constraint satisfaction problem, we study the clones of idempotent polymorphisms of certain digraph classes. Our first results are two algebraic dichotomy, even "gap",…

Computational Complexity · Computer Science 2015-05-13 Catarina Carvalho , Florent Madelaine , Barnaby Martin

A lattice Delaunay polytope P is called perfect if its Delaunay sphere is the only ellipsoid circumscribed about P. We present a new algorithm for finding perfect Delaunay polytopes. Our method overcomes the major shortcomings of the…

Number Theory · Mathematics 2016-11-17 Mathieu Dutour , Konstantin Rybnikov

Symmetric edge polytopes are a class of lattice polytopes constructed from finite simple graphs. In the present paper we highlight their connections to the Kuramoto synchronization model in physics -- where they are called adjacency…

Combinatorics · Mathematics 2022-09-02 Alessio D'Alì , Emanuele Delucchi , Mateusz Michałek

This is the first one of a series of papers on association of orientations, lattice polytopes, and abelian group arrangements to graphs. The purpose is to interpret the integral and modular tension polynomials of graphs at zero and negative…

Combinatorics · Mathematics 2007-06-25 Beifang Chen

In this paper we give two characterisations of the class of reflexive graphs admitting distributive lattice polymorphisms and use these characterisations to address the problem of recognition: for a reflexive graph G in which no two…

Combinatorics · Mathematics 2018-01-30 Mark Siggers

Starting from any finite simple graph, one can build a reflexive polytope known as a symmetric edge polytope. The first goal of this paper is to show that symmetric edge polytopes are intrinsically matroidal objects: more precisely, we…

Combinatorics · Mathematics 2023-07-12 Alessio D'Alì , Martina Juhnke-Kubitzke , Melissa Koch

In this paper we investigate the number of integer points lying in dilations of lattice path matroid polytopes. We give a characterization of such points as polygonal paths in the diagram of the lattice path matroid. Furthermore, we prove…

Combinatorics · Mathematics 2017-10-26 Kolja Knauer , Leonardo Martínez-Sandoval , Jorge Luis Ramírez Alfonsín

A lattice polytope translated by a rational vector is called an almost integral polytope. In this paper we investigate Ehrhart quasi-polynomials of almost integral polytopes. We study the relationship between the shape of the polytopes and…

Combinatorics · Mathematics 2023-08-31 Christopher de Vries , Masahiko Yoshinaga

A lattice Delaunay polytope is known as perfect if the only ellipsoid, that can be circumscribed about it, is its Delaunay sphere. Perfect Delaunay polytopes are in one-to-one correspondence with arithmetic equivalence classes of positive…

Metric Geometry · Mathematics 2007-05-23 Mathieu Dutour , Robert Erdahl , Konstantin Rybnikov

Lattice polytopes which possess the integer decomposition property (IDP for short) turn up in many fields of mathematics. It is known that if the Cayley sum of lattice polytopes possesses IDP, then so does their Minkowski sum. In this…

Combinatorics · Mathematics 2022-01-26 Takayuki Hibi , Hidefumi Ohsugi , Akiyoshi Tsuchiya

Let $G$ be a finite graph allowing loops, having no multiple edge and no isolated vertex. We associate $G$ with the edge polytope ${\cal P}_G$ and the toric ideal $I_G$. By classifying graphs whose edge polytope is simple, it is proved that…

Commutative Algebra · Mathematics 2018-08-22 Hidefumi Ohsugi , Takayuki Hibi